I've been following the various examples including this OpenLayers: Get Coordinates of drawn features and this https://openlayers.org/en/master/examples/snap.html
and have produced the code below (note in custom projection).
How can I view the coordinates for a drawn point or polygon in a web page?
And even better store them so they can go into a database?
From the old post I can see that the answer involves going back the vector layer and storing the geometries in a new araay, but can't work out the next steps to view in page and save.
import 'ol/ol.css';
import Map from 'ol/Map.js';
import View from 'ol/View.js';
import {Draw, Modify, Select, Snap} from 'ol/interaction.js';
import {Tile as TileLayer, Vector as VectorLayer} from 'ol/layer.js';
import {TileWMS, Vector as VectorSource} from 'ol/source.js';
import WMTSCapabilities from 'ol/format/WMTSCapabilities.js';
import WMTS, {optionsFromCapabilities} from 'ol/source/WMTS.js';
import {getWidth, getCenter} from 'ol/extent.js';
import {get as getProjection} from 'ol/proj.js';
import {register} from 'ol/proj/proj4.js';
import {format} from 'ol/coordinate';
import proj4 from 'proj4';
import {Circle as CircleStyle, Fill, Stroke, Style} from 'ol/style.js';
proj4.defs('EPSG:27700', '+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 ' +
'+x_0=400000 +y_0=-100000 +ellps=airy ' +
'+towgs84=446.448,-125.157,542.06,0.15,0.247,0.842,-20.489 ' +
'+units=m +no_defs');
register(proj4);
var proj27700 = getProjection('EPSG:27700');
proj27700.setExtent([0, 0, 700000, 1300000]);
var raster =
new TileLayer({
source: new TileWMS({
url: 'myserver',
params: {'LAYERS': 'mylayer', 'TILED': true},
transition: 0,
serverType: 'bla'
})
});
var vector = new VectorLayer({
source: new VectorSource(),
style: new Style({
fill: new Fill({
color: 'rgba(255, 255, 255, 0.2)'
}),
stroke: new Stroke({
color: '#ffcc33',
width: 2
}),
image: new CircleStyle({
radius: 7,
fill: new Fill({
color: '#ffcc33'
})
})
})
});
var map = new Map({
layers: [raster, vector],
target: 'map',
view: new View({
projection: 'EPSG:27700',
center: [408188, 308846],
zoom: 9
})
});
var ExampleModify = {
init: function() {
this.select = new Select();
map.addInteraction(this.select);
this.modify = new Modify({
features: this.select.getFeatures()
});
map.addInteraction(this.modify);
this.setEvents();
},
setEvents: function() {
var selectedFeatures = this.select.getFeatures();
this.select.on('change:active', function() {
selectedFeatures.forEach(function(each) {
selectedFeatures.remove(each);
});
});
},
setActive: function(active) {
this.select.setActive(active);
this.modify.setActive(active);
}
};
ExampleModify.init();
var optionsForm = document.getElementById('options-form');
var ExampleDraw = {
init: function() {
map.addInteraction(this.Point);
this.Point.setActive(false);
map.addInteraction(this.LineString);
this.LineString.setActive(false);
map.addInteraction(this.Polygon);
this.Polygon.setActive(false);
map.addInteraction(this.Circle);
this.Circle.setActive(false);
},
Point: new Draw({
source: vector.getSource(),
type: 'Point'
}),
LineString: new Draw({
source: vector.getSource(),
type: 'LineString'
}),
Polygon: new Draw({
source: vector.getSource(),
type: 'Polygon'
}),
Circle: new Draw({
source: vector.getSource(),
type: 'Circle'
}),
getActive: function() {
return this.activeType ? this[this.activeType].getActive() : false;
},
setActive: function(active) {
var type = optionsForm.elements['draw-type'].value;
if (active) {
this.activeType && this[this.activeType].setActive(false);
this[type].setActive(true);
this.activeType = type;
} else {
this.activeType && this[this.activeType].setActive(false);
this.activeType = null;
}
}
};
ExampleDraw.init();
optionsForm.onchange = function(e) {
var type = e.target.getAttribute('name');
var value = e.target.value;
if (type == 'draw-type') {
ExampleDraw.getActive() && ExampleDraw.setActive(true);
} else if (type == 'interaction') {
if (value == 'modify') {
ExampleDraw.setActive(false);
ExampleModify.setActive(true);
} else if (value == 'draw') {
ExampleDraw.setActive(true);
ExampleModify.setActive(false);
}
}
};
ExampleDraw.setActive(true);
ExampleModify.setActive(false);
var snap = new Snap({
source: vector.getSource()
});
map.addInteraction(snap);
Best Answer
Probably best done by listening for drawend events on each of your draw interactions:
... and since you are also using a modify interaction: